I have to respectfully disagree with the core of your argument, Murilo. I don't think party communication in TDM is nearly as important as you claim. I can respect the logic, and in some cases it might hold true to an extent, but by and large, TDM is completely skill based, and being in a party doesn't add much, especially in core mode. For HC mode without ready access to radar, team play and communication is much more pronounced. But in core mode, I get just as much info, actually a lot more info, from spy planes, sounds (gunshots and footsteps), unsilenced red blips on radar, disappearing teammate triangles, etc as I do from our team, and we are a damn good team when we all get together, with great communication when it's needed. But, the amount of information you can get from your radar and game sounds, if you pay proper attention, absolutely dwarfs the info from your team about "there's a guy over there" or whatever. This is not true for other modes, but for TDM, it is by far my experience. I do not play any better in TDM when I'm on a team with good communication, vs the same skilled team without communication. I do hate getting put on a team with noobs and losing when I do really well, but I never blame communication in TDM, because I just don't think it has nearly as much to do with it as you do.
Now, that is all with respect to party communication, as you were arguing was the problem. I disagree with that. I think the problem you ran into is just that you had a lot of good players playing together. I don't disagree that a party full of really good players will absolutely DESTROY noobs. We do this all the time, only it's not our communication that accomplishes it. Most of the time we are talking about something non COD related, or just cracking jokes. The reason a team full of good players is a problem, even without good communication, is because the better players have very good situational awareness as I described above, paying attention to radar, sounds, etc. No one needs to tell me where the enemy is. When a teammate dies, 9 times out of 10 I know right where that teammate was on the map, which direction they were facing, etc, and based on the direction he was facing, my knowledge of the map, and the sounds I heard, I will head straight there and know just where to look for the enemy, what gun the enemy was using, a good estimate on whether or not that enemy is reloading, which enemy it was (was it a good player?), where they might be headed, etc. This is all without any input from teammates. Half the time, even if a teammate says "He's over there", before he can finish, we just say back "he's already dead." And it's not because they told us where the enemy was. Now, in normal games there might be one maybe two players like this on the enemy team. They can be a pain, but don't necessarily dictate the victory. But if you have 6 of them doing this, that's freakin hard to overcome, whether they communicate with each other or not.
So this is all to agree that playing against a team of good players sucks and is hard/impossible/a problem, but I want to clarify that it has very little or nothing to do with them telling each other where you are. At least, in my opinion.
And FWIW, I never play mercenary mode because it is harder IME. All of the good players who want to play solo think they are smart by playing merc mode, but in reality, it's just full of all the smart good players, lol. Because BLOPS allows guests, and the guests can only play in the regular TDM lobby, and because 99.99% of the time the guests are terrible (and so are the hosts), I prefer to play against these noobs, and the other noobs who don't even know what merc mode is. You might run into a group of really good players every once in a while, but that is quite rare IME. I can almost count on one hand the number of teams I've faced where more than 2 of them had a kd above 2, in the couple thousand matches I've played and probably 20 days of play time (or whatever it is). It sucks bad when you do, but it's rare enough that it doesn't really bother me.